Study on the Inclusion Interactions of (3-Cyclodextrin with Oleic Acid by Competitive Inclusion Method

摘要

The grinding wheel will have a property of self-lubricating when the inclusion complexes of pcyclodextrin (P-CD) and oleic acid are used as filler. The association constants and thermodynamic parameters of inclusion complex of P-CD and oleic acid were determined by competitive inclusion method in aqueous buffer solution (pH = 10.50, c = 0.025 mol/L) at different temperatures using phenolphthalein (PP) as a probe. Furthermore, the stoichiometric ratio of the complex was derived by equimolar series method. The results showed that the stoichiometric ratio of the complex was about 1:1 and the thermodynamic parameters of AG, dH and AS were all negative, which indicated that the formation of the inclusion complex was spontaneous, exothermic and enthalpy-driven. Thermogravimetric analysis revealed that the complex began to have a weight loss at 300°C and could withstand the hardening temperature of resin bond grinding wheel.